Another Airbnb guest has found hidden cameras in their rental home — this time disguised as motion detectors — raising questions as to what the platform and its customers can do to ensure privacy.

The short-term leasing service defended itself after a particularly viral tweet erupted online last week, showing a "motion detector" found in an Airbnb home that, upon closer inspection, was actually a camera.

With over 20,000 retweets, hundreds of people replied to American archivist Jason Scott's tweet. Scott, whose unnamed colleague was the person who actually uncovered the secret IP (internet protocol) camera, included photos of the device.

Airbnb spokesperson Jeff Henry told BuzzFeed News this type of incident was "incredibly rare" and that the company had permanently banned the host from its community. A full refund was also offered to the guest.

"Cameras are never allowed in bathrooms or bedrooms; any other cameras must be properly disclosed to guests ahead of time," Henry said.

This incident is one of several accounts of unsavoury Airbnb surveillance in recent years.

In October, an Indiana couple visiting Florida discovered a hidden camera disguised as a smoke detector in their Airbnb's master bedroom.

As part of the company's own policy, Airbnb hosts must fully disclose any security cameras on the listing and get consent where required.

In some cases, people say they have been afraid to come forward after finding hidden cameras in their rented Airbnbs, because they had shared personal information with the host.

BuzzFeed News spoke with two people who allege they found hidden cameras in their Airbnbs. One did not want their name disclosed publicly, or to push the matter further with Airbnb, because they were scared of the host.

"I would love to see Airbnb take this seriously, but not if it means bringing that stress back into our lives," they said.

The other accuser, a woman named Erin, recounted the tumultuous process she says she went through after discovering a hidden camera in the bedroom of an Airbnb in Houston, Texas, earlier this year.

After arriving at the rental and finding the camera, Erin texted friends about it but did not immediately report the matter to Airbnb. "I don't know what I was thinking, I was just so tired," she said.

Erin continued to stay at the Airbnb and encountered no problems, but within an hour of checking out she received a message saying the host had accused her of causing damage. The host said Erin had thrown a party, trashed the place, and also mentioned she had unplugged security cameras. "Because he reported me for damage they just treated it like I was trying to get out of paying," she said.

But the host's admission that there were security cameras in the property allowed Erin to push the matter further.

"I was like, 'Hello, he is saying he did what I was saying he did', and the customer service rep told me that I should 'respond professionally'," said Erin.

Frustrated, Erin took to Twitter to complain and says she was immediately contacted by Airbnb's trust and safety team and asked specifically about the cameras. Unfortunately, Erin did not take any photos. "Those conversations didn't go very far," she said.

Eventually, Erin says, she was told the host's listings had been "sequestered." She received no apology and no initial refund, but the company did later conduct an internal review of the whole process and refund her in full.

"It was really scary because this dude knows where I live, my full name, my cell number," said Erin. "But at the same time I know his full name and number, too, so I figured that kind of protects me.

"He texted me a lot while I was in Houston. It was kind of a lot looking back and I think he was kind of taking my temperature after he noticed the cameras were unplugged."

Hidden cameras aren't just an issue for Airbnb — it's been a hot-button topic in hospitality for years. There are hundreds of stories about hotels using unlawful surveillance.

Airbnb recommends its customers read the reviews of the host of any rental property they might be interested in, and also offers an on-platform messaging tool that allows communication between host and guests. However, there is only so much Airbnb can do.

While all hosts are required to declare any cameras they may have in common areas, there is nothing the company can do to stop people, well...being people.

Brad Esposito is a news reporter for BuzzFeed and is based in Sydney, Australia.